Nozzle

ABSTRACT

An elongated hollow body formed of a resiliently yieldable material having a bore therethrough. A thread formation of helical configuration is formed in the bore and the bore tapers gradually toward its outlet end. Passages formed in the inlet end of the nozzle are variable in size to control the rate of liquid flow into the bore.

Unlted States Patent 1 1 1111 3,788,353 Breunsbach Jan. 29, 1974 [54]NOZZLE 371,158 /1887 Wright 137 604 3,104,826 9/1963 Morris 239/417 X[75] Inventor: $3 Breunsbach Hamburg 3,540,474 11/1970 Sharples 137/604x [73] Assignee: Spirolet Corporation, North FOREIGN PATENTS ORAPPUCAUONS Tonawanda, 603,869 1/1926 France 239/398 1,170,934 9/1958France 239/398 [22] Filed: Apr. 24, 1972 [21] Appl. N0.: 247,207 PrimaryExaminerRobert G. Nilson Related U S Application Data Attorney, Agent,or Firm-Edwin T. Bean, Jr. [62]. Division of Ser. No. 7,747, Feb. 2,1970, Pat. No.

3,692,243. [57] ABSTRACT 52 us. c1 137 604 239 417 ekmgaed formed Ofresiliemly is 1i 1m. 01. F1 6k 1 9/00 Yieldable material having a boreherethrough A 5 Fi of Search 7 thread formation Of helical configuration18 formed in 239/4173 the bore and the bore tapers gradually toward itsoutlet end. Passages formed in the inlet end of the nozzle [56]References Cited are variable in size to control the rate of liquid flowUNITED STATES PATENTS the bore 3,470,826 10/1969 Foulds 137/604 X 6Claims, 14 Drawing Figures NOZZLE This application is a division ofapplication Ser. No. 7747 filed Feb. 2, 1970 now US. Pat. No. 3,692,243.

BACKGROUND OF THE INVENTION This invention relates to nozzles and, moreparticularly, to nozzles for cement guns used in handling cementitiousmaterials.

In cement guns a mixture of cementitious material in dry particle formis pneumatically blown through a metal nozzle which can have a rubberlining. In its passage through the nozzle, water is introducedtransversely into the stream of dry material and mixed therewith to forma wet cementitious material which issues through the nozzle as a highvelocity stream to be directed upon a background surface. In thismanner, the cementitious material is pneumatically impacted against thesurface to form a dense cementitious mass. One use for such cement gunnozzles is in applying a linging to the refractory walls of a hightemperature furnace.

A tremendous amount of static electricity is generated during thespraying or blowing operation when using conventional nozzles, requiringcareful grounding procedures. Moreover, they are susceptible to wearcaused by the abrasive action of the material passing through thenozzle. Also, the wet mixture issuing from these nozzles tends tospread, making accurate application extremely difficult and resulting inexcessive wastes of the mixture and contamination of the ambientatmosphere. Furthermore, proper mixing is not always obtained when usingconventional nozzles. Unless a thorough mixing of the cement ingredientsand water is effected, there is an excess of rebound, a term commonlyused to designate that portion of the cementitious material which doesnot adhere to the background surface, but instead is reflected and lost.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a cement gun nozzle which effectively overcomes the above-noteddisadvantages.

It is another object of this invention to provide the foregoing in anozzle which is competitive in cost, durable and dependable inoperation, and easy to use.

It is a further object of the present invention to provide the foregoingnozzle with improved liquid flow control means to realize a consistentand uniform mixture.

In one aspect thereof, the cement gun nozzle of this invention ischaracterized by being formed in its entirety of a plastic resilientlyyieldable material, preferably formed of but not restricted to urethane.The bore of the nozzle is provided with a thread formation of agenerally helical pattern to impart a spiral twist or rifling motion tothe mix as it passes through the nozzle. Also, the bore tapers slightlytoward the outlet end to choke the material issuing from the nozzle andprevent spreading. Resiliently yieldable passages are formed in theinlet end of the nozzle for adjusting the sizes thereof to control therate of liquid flow into the bore of the nozzle.

The foregoing and other objects, advantages and characterizing featuresof the present invention will become clearly apparent from the ensuingdetailed description of certain illustrative embodiments thereof, takentogether with the accompanying drawings wherein like referencecharacters denote like parts throughout the various views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of anozzle of the present invention, shown attached to a material conveyingconduit;

FIG. 2 is a vertical sectional view taken about on line 22 of FIG. 1;

FIG. 3 is a vertical sectional view taken about on line 33 of FIG. 1;

FIG. 4 is a longitudinal sectional view of the nozzle of FIG. 1 shown inthe mold employed for forming such nozzle;

FIG. 5 is a fragmentary sectional view, on an enlarged scale, showing ahose coupling connected to the inlet end of the nozzle of FIG. 1;

FIG. 6 is a fragmentary sectional view of a second form of nozzle ofthis invention;

FIG. 7 is a longitudinal sectional view, on a reduced scale, of thenozzle of FIG. 6 shown in a mold for its formation;

FIG. 8 is a fragmentary sectional view of a third form of nozzle of thisinvention;

FIG. 9 is a fragmentary sectional view of a fourth form of nozzle ofthis invention;

FIG. 10 is a fragmentary, longitudinal sectional view of a nozzledepicting a thread formation in the bore thereof common to the forms ofnozzles shown in FIGS. 1, 6, 8 and 9;

FIG. 11 is a longitudinal sectional view of still another form of nozzleof this invention shown attached to a liquid injecting adaptor;

FIG 12 is a longitudinal sectional view of the nozzle of FIG. 11 shownenclosed in a mold;

FIG. 13 is a side elevational view, partially in section, of the liquidinjecting adaptor of FIG. 11; and

FIG. 14 is an end elevational view of the liquid injecting adaptor ofFIG. 13 looking in the direction of arrows 14-14.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS Referring in detail tothe drawings, there is shown in FIG. 1 a presently preferred form ofnozzle, constructed in accordance with this invention and generallydesignated 20. Nozzle 20 is shown attached to a hose coupling, generallydesignated 22, which is connected to a conduit 24 through which drycement ingredients from a suitable source (not shown) are directed by ablower (not shown) in a manner known in.

the art. Such material is forced under pressure through conduit 24, hosecoupling 22 and into and through nozzle 20. Liquid, usually water, isadded to the material by means of a pipe 26 connected into nozzle 20.The dry material and water are intermixed to produce a wet cementitiousmaterial which is directed through nozzle 20 and outwardly therefromonto the desired surface.

Nozzle 20 is composed of a resiliently yieldable elastomeric material,preferably urethane, which is wear and abrasion resistant andsufficiently rigid to accurately guide a stream of material in theintended direction. Nozzle 20 is of a unitary, one-piece constructionand can be of any convenient size suitable for a particular application.

Nozzle 20 comprises an elongated hollow body 28 having an inlet end 30and an outlet end 32. The inlet end of nozzle 20 is generally bellshaped as indicated at 34 and has an inwardly inclined neck portion 36which merges into the reduced outside diameter portion 38 of nozzle 20.Portion 38 is slightly tapered toward outlet end 32 and is provided withtwo pairs of diametrically opposed lugs 40 and 42 for facilitating thegrasping and handling of nozzle 20. A metal reinforcing ring 44 (FIGS. 4and can be embedded in bell shaped portion 34, if desired.

Nozzle is provided with an axial bore 46 (FIGS. 3 and 5) having a firstportion provided with a cylindrical wall surface 48 adjacent inlet end30, an elongated intermediate portion in which a thread formation 50 ofa double helical configuration is formed in the wall surface thereof,and an outlet portion having a cylindrical wall surface 52. Theintermediate portion of bore 46 tapers slightly inwardly from inlet end30 toward outlet end 32. The helical configuration of bore 46 togetherwith the axial taper thereof constitute important features of thisinvention, imparting a spiral twist to the cementitious ingredients toprovide a consistent and thorough mix and emulsification of suchingredients. The taper of bore 46 maintains control and tends to chokethe cementitious mix as it is directed outwardly through nozzle 20 tominimize spreading of such mix.

Portion 34 of nozzle 20 is provided with a threaded opening 54 forreceiving hose coupling 22 (FIG. 5). Opening 54 terminates in an endwall 58 which serves as a seat for coupling 22. An annular recess 60extends axially inwardly of end wall 58, providing a liquid manifold anddefining an inner wall portion 62 having an end face 64 lying in atransaxial plane slightly offset axially inwardly from the transaxialplane of end wall 58. End face 64 is beveled to form an inclinedshoulder 66 for a reason that will hereinafter become apparent. Anannular recess 68 is disposed at the juncture of end wall 58 and theside wall of opening 54 to provide a relief for accommodating radialexpansion of the resiliently yieldable material in the area of end wall58 upon compression of the same by hose coupling 22.

A boss or projection 70 extends radially outwardly from bell-shapedportion 34 of nozzle 20 and is provided with a tapped opening 72 forreceiving pipe 26 connected to a suitable source of liquid (not shown).Opening 72 communicates with a passage 74 leading to recess 60. A metalreinforcing ring 45 can be embedded in projection 70.

In use, hose coupling 22 is threaded into opening 54 until the end face76 of coupling 22 is seated against end wall 58 as shown in FIG. 5. Aninternal flange or boss 77 projects axially from end face 76 of coupling22 and has an outer wall surface 78 overlying shoulder 66 and inclinedinwardly at an angle corresponding to the angle of inclined shoulder 66.With end face 76 in initial abutting angagement with end wall 58,surface 78 is slightly spaced from shoulder 66 to form an annularpassage 80 leading into bore 46. Also, the spacing between end face 76and face 64 forms an annular communicating passage 82 between 80 andrecess 60. Thus, water can be directed radially inwardly into bore 46via bore 72, passage 74, annular recess 60 and passages 82 and 80.

During the blasting operation, a cement mixture in dry powder form isforced under pneumatic pressure through conduit 24 and hose coupling 22into bore 46 of nozzle 20. Simultaneously, a liquid, such as water,under pressure is introduced into bore 46 through opening 72, passage74, recess 60 and passages and 82. The water is mixed with the cementparticles passing through bore 46 in portion 48 to form a wetcementitious admixture. Thread formation 50 imparts a spiral twisting orrifling motion to the admixture to thoroughly intermix the ingredientsand obtain the proper consistency and density. The rifling motionbecomes progressively shallower toward the outlet end 32 and provides achoking action, the result of which is an efiiciently controlled streamof cement emulsion directed at a high velocity against a backgroundsurface with relatively little rebound and relatively no dustcontamination of the ambient atmosphere.

A significant feature of the nozzle of this invention is the water flowcontrol means located at the inlet end of nozzle 20. At the initialstage of the blasting operation, the nozzle operator can thread coupling22 relative to nozzle 20 in such a manner as to obtain an optimum waterflow pattern. If the material issuing from nozzle 20 is too wet,coupling 22 is threaded further into opening 54 to compress end wall 58thereby decreasing the size of passages 80 and 82 to restrict the flowof water therethrough. If the issuing material is not sufficientlywetted, coupling 22 can be threaded outwardly of opening 54 to enlargepassages 80 and 82 as required. These adjustments are made quickly andeasily by the operator who need only rotate coupling 22 with one handwhile holding nozzle 20 with the other. The coupling and nozzle areself-locking in adjusted position, being held therein by the resilientreaction of end wall 58. Thus, a sensitive water flow control means isprovided to produce a highly controlled cementitious material with verylittle rebound and dust. It has been found that only about 6 percent ofmaterial loss is occasioned by rebound with the nozzle of the presentinvention as contrasted to a 2030 percent rebound loss effected byconvention nozzles. Although the nozzle of the present invention ispreferably used for the pneumatic application of wet cementitiousmaterial, it can also be used for dispensing dry materials.

Coupling 22 and nozzle 20 preferably are made of the same material,polyurethane, which material is highly resistant to the abrasive actionof the cementitious material passing therethrough, and to the generationof static electricity normally accompanying such passage. However,nozzle 20 can be used with couplings formed of any material, such asmetal couplings for example, which are widely used in industrialapplications.

With reference to FIG. 4, the foregoing nozzle construction is made by amold pouring process in the following manner:

An end core member having a central square opening is slip fitted overthe square end of a core piece 92. Core piece 92 has an elongated bodyprovided with a double helical rib 94 for forming the thread formation50 in the finished nozzle 20. Member 90 is provided with externalthreads 96, a first annular ring 98 and a second annular ring 100 forforming threaded opening 54, recess 60 and relief recess 68,respectively, in the finished product.

A base plate 102 is slipped over a complimentary sized reduced portion104 of end core member 90 with a locating pin 106 disposed between coremember 90 and base plate 102 for properly aligning the same. A

nut 108 is threaded onto the threaded end portion 110 of core piece 92.A reinforcing ring 44 is set on base plate 102. Outer mold splitsections 112 and 114, having handles 116 and 118, are placed over corepiece 92 and spaced therefrom by means of locating pin 120. A slideclamp ring 122 is slipped over the smaller end of assembled sections 112and 1 14 and is tightened about the composite outer mold by slidingclamp ring 122 longitudinally along the same. A threaded plug 124 isinserted radially into the enlarged portion of mold section 114 with thefree end of plug 124 abutting annular ring 98. Plug 124 forms tappedopening 72 and passage 74 in the finished nozzle 20. A mandrel bushing125 is placed over core piece 92 between mold sections 112 and 1 14. Aclamp member 126 is placed over the other end of sections 112 and 114and held in place by a nut 128 threaded onto the threaded end portion130 of core piece 92.

Prior to assembling the above mold assembly,'the parts are coated with asuitable lubricant or mold releasing agent. After the mold is assembledand heated, urethane in plastic pliable form and at the proper durometeris poured into the mold assembly around clamp 126. After pouring, themold assembly is oven cured at the correct temperature for a given timeto enable the urethane material to set. After the material has set, themold assembly is stripped leaving the finished nozzle 20. Afterstripping, the nozzle is heat cured.

Reinforcing ring 44 is supported in the mold as by projections engagingplate 102 and threads 96 of member 90, and ring 45 is supported byengagement with plug 124.

FIGS. 6 and 7 illustrate another form of nozzle of the present inventionwhich is very similar to the above described form with the exceptionthat the passages forming the water control means are orienteddifferently. All of the other structural features and their resultantadvantages including the helical threaded formation and the gradualtaper of the nozzle fore are duplicated in the form of the inventionillustrated in FIGS. 6 and 7 and the same numbers primed are used toidentify elements similar to those used in the first form describedabove.

As shown in FIGS. 6 and 7, passage 74' of nozzle communicates with anannular manifold passage 132 which communicates with a passage 134extending radially inwardly at an angle to wall surface 48' in thedirection of the outlet end of nozzle 20 and opening into bore 46.Passage 132 encircles a sleeve 133 defining passage 134 at one end andseat 58 at the other, which sleeve is joined to nozzle portion 34' by ahinge portion 135. The opening provided by passage 134 can be varied asrequired or desired by threading hose coupling 22 into opening 54' withcoupling 22 in abutting relation with seat 58' of nozzle 120. Theurethane material of hinge 135 will yield resiliently under compressionto vary the size of passage 134. An annular relief recess 68' isprovided around seat 58 to further define hinge 135 and to accommodatethe expansion of material in the area of seat 58'.

Passages 132 and 134 are formed in nozzle 20 during the molding thereofby employing a cup-shaped annular member 136 formed of a eutectic metal.As shown in FIG. 7, member 136 is inserted in an annular groove 138provided about the periphery of end core member 90 with plug 124engaging the outer annular wall portion of member 136. Although the moldassembly depicted in FIG. 7 differs somewhat from the mold assemblydescribed in connection with the forming of nozzle 20, the variationsare slight and the operation thereof obvious in view of the foregoingwhereby it is believed that no detailed description or amplification isnecessary, the important factor being that member 136 is positioned inthe mold assembly prior to the pouring operation.

After the urethane material has been poured and partially set, the moldassembly is stripped. After end core member and plug 124' have beenremoved from the mold assembly, the lip portion of member 136, i.e.,that portion which was disposed in annular groove 138, is removed bymeans of a ream cutter so that core piece 92 can be screwed leftwardlyout of the mold assembly. Nozzle 20 with member 136 embedded therein isthen placed in an oven and heated to 270 F. for a few minutes to meltmember 136. The melted alloy flows outwardly through passage 74' and afitting inserted in bore 72'. Nozzle 20' is then placed in an oven forfinal curing.

FIG. 8 illustrates a third form of nozzle of this invention andcomprises a two-piece composite nozzle 20" preferably formed of urethaneand consisting of an outer shell 140 having an outer configurationsimilar to the above described nozzles. Shell 140 is provided with aboss 142 having a tapped opening 144 communicating with a passage 146extending through the wall of shell 140. Shell 140 is provided with abore 148 having a double helical thread formation 150 therein similar tothe threaded bores of the outer nozzles previously described.

An insert 152, preferably also formed of urethane, is fitted into theinlet end of shell 140 and has a shoulder 154 in abutting engagementwith an annular shoulder 156 provided adjacent the inlet end of shell140. Insert 152 has an outer peripheral surface conforming to the innerwall surface of shell 140 adjacent its inlet end and secured thereto bya suitable adhesive 158. A metal reinforcing ring 160 is embedded inshell 140 and serves to reinforce and rigidify the inlet end of nozzle20". A reinforcing ring 145 is embedded in boss 142.

Insert 152 is provided with an opening 162 defined by a threaded wallportion 164 and terminating in an end face 166 which serves as the seatfor hose coupling 22. An annular recess 168 is provided at the junctureof wall portion 164 and end face 166 for the purpose of accommodatingmaterial expansion during the compression of insert 152 by means of ahose coupling threaded into opening 162 and to further define a hingesection 167 corresponding to hinge 135 of FIG. 6. A bore 170 is providedin insert 152 and has approximately the same diameter as bore 148.Insert 152 has a tapered inner end portion 172 conforming generally tothe taper of an inclined shoulder 174 provided on the inner wall surfaceof shell 140. The spacing between portion 172 and shoulder 174, whichoverlap, defines a passage 176 opening into bore 148 and communicatingwith a manifold passage 178 connected to passage 146. Thus, water orother suitable liquid is directed into bore 148 via opening 144, passage146 and passages 178 and 176. The rate of flow can be controlled byadjusting the size of passage 176 which is accomplished by threading ahose coupling 22 in opening 162 against seat 166, the hinge 167resiliently yielding to permit end portion 172 to move toward shoulder174.

A fourth form of nozzle of this invention is disclosed in FIG. 9 and issimilar in its use of an insert to the form shown in FIG. 8. However,the water flow passages are differently oriented. The other structuralfeatures are identical and will be identified by the same numbers primedused to identify corresponding structure in the form of the inventionshown in FIG. 8.

As shown in FIG. 9, the inner end of insert 152' terminates in a flatface 180 normally slightly spaced axially from a flat, annular shoulder182 provided on shell 140' to define a passage 184 therebetweenextending radially inwardly normal to wall surface 148' of shell 140.Passage 184 communicates with a manifold passage 178' leading to asuitable source of liquid (not shown) via passages 146' and opening144'. The rate of water flow is adjusted by varying the opening ofpassage 184 by moving insert 152 axially relative to shell 140' throughthe threaded connection of a hose coupling 22 with opening 162. Theresilient material of the nozzle adjacent shoulder 158 yields toaccommodate this.

It should be noted that all forms of nozzles heretofore described have acommon bore 46 extending therethrough as shown in FIG. 10. Threadformation 50 which effects a rifling action of the mix is defined by aforward or leading wall 51 substantially normal to the flat, recessedinner wall 55 and a generally inclined rearward or trailing wall 53.Although a thread formation of a double helical configuration ispreferred, it should be understood that a single helical threadformation can be used, if desired, and arranged at any suitable pitchwithin the purview of this invention. Likewise, the walls definingrecesses 55 can be oriented at any desired angle relative to thelongitudinal axis of bore 46. It will be noted that the height of thethread, i.e. the distance from recessed surface 55 to land surface 57progressively diminishes in the direction of taper.

Still another form of nozzle assembly of this invention is shown inFIGS. 11l4 and comprises a separate nozzle, generally designated 200,attached to a liquid injection adaptor, generally designated 202 (FIG.11), both of which preferably are formed of urethane.

Nozzle 200 comprises an elongated, hollow body 204 having an axial bore206 therethrough, and an inlet end 208 and an outlet end 210. Bore 206is provided with a thread formation 212 of a double helical pattern.Although each incremental width of the teeth defining thread formation212 flares outwardly, the thread formation becomes progressivelyshallower toward outlet end 210 to gradually constrict bore 206 for areason that will hereinafter become apparent. The outside diameter ofbody 204 also tapers slightly from inlet end 208 to outlet end 210. Twopair of diametrically opposed lugs 214 are provided on the outer surfaceof body 204 for facilitating the handling and manipulation of nozzle200. Inlet end 208 is provided with an externally threaded portion 216for receiving adaptor 202 thereon.

Adaptor 202 comprises a generally cylindrical body 220 having a bore 222and an enlarged diameter internally threaded opening 224 for receiving asuitable hose coupling, such as identified in FIG. 1 as 22. A boss 226extends radially outwardly from body 220 and is provided with a tappedopening 228 communicating with a radial passage 230 connected to anannular recess 232 formed in body 220 and defining a sleeve orcollar-like wall 234. The inner axial end of wall 234 is provided with acircular shoulder or seat 236 having a series of projections in the formof teeth 238 extending circumferentially thereabout and inclinedrelative to the transaxial plane of adaptor 202. A threaded opening 240is provided at the outlet end of adaptor 202 for receiving threadedportion 216 of nozzle 200. A pair of axially spaced metal rings 242 areprovided in body 220 to reinforce and rigidify the same. A ring 245 isprovided in boss 226.

In use, nozzle 200 is threaded into adaptor 202 until the inlet end face208 of nozzle 200 engages seat 236. A suitable conduit or hose isconnected into threaded opening 224 for conveying dry cement ingredientsin powder form into adaptor 202. A suitable coupling is threaded intoopening 228 for connecting adaptor 202 to a suitable source of liquidunder pressure. The dry cement mixture is mixed with water introducedinto adaptor 202 via opening 228, passage 230, recess 232 and thepassages defined by teeth 238 to form a wet cementitious admixture.Thread formation 212 imparts a spiral twisting or rifling motion to theadmixture as it is forced under pressure through nozzle 200. Thisrifling action coupled with the choking action caused by the threadformation becoming shallower toward the outlet end of nozzle 200 resultsin a highly controlled delivery of the wet cementitious material withvery little rebound and dust.

In order to control the water flow rate for obtaining the optimum mixdensity and consistency, the operator need only thread adaptor 202axially relative to nozzle 200 to bring seal 236 into engagement withthe inlet end face 208 of nozzle 200 with varying degrees ofcompression. Because of the resiliency of the material of which adaptor202 is formed, teeth 238 will flex and yield resiliently undercompression and the passages therebetween will correspondingly vary insize to control the rate of water flow therethrough.

Although teeth 238 are preferably inclined to the transaxial plane ofnozzle 200 to provide a very sensitive control, it should be understoodthat teeth 238 can be of square formation. Although nozzle 200 and waterinjection adaptor 202 are preferably formed of urethane, any suitableresiliently yieldable material of sufficient durometer and density, canbe used in lieu of urethane, if desired. Of course, nozzle 200 can beused to convey dry material, if desired.

It should be appreciated that liquid injection adaptor 202 can be usedindependently with other conventional nozzles, if desired. Likewise,nozzle 200 is not restricted in use with adaptor 202 but has utilitywith any suitable liquid injection adaptor or head.

FIG. 12 illustrates the mold assembly used in forming nozzle 200, suchmold assembly comprising a pair of split mold sections 250 and 252, anend plate 254 having a central opening therein for receiving the reduceddiameter end portion 256 ofa core piece 258, to which it is soldered.Core piece 258 is provided with a spiral rib formation 260 preferably ofa double helix pattern formed about the periphery of core piece 258 toimpart the desired thread formation to the finished nozzle. A mandrelsleeve 262 is slipped over a cylindrical portion of core piece 258 andis held in place by a clamp member 264 also encircling the cylindricalportion of core piece 258. A wing screw 266 is threaded into the endface of core piece 258 to clamp and secure the assembly together. A pairof handles 268 and 270 are secured to mold sections 250 and 252 forfacilitating the handling of the mold assembly.

It should be noted that thread formation 212 of nozzle 200 varies inconfiguration from that of the thread formation of the previouslydescribed nozzles. The specific thread shape and pitch can vary witheach nozzle within the purview of this invention as dictated by theeconomics of design and the particular application of the nozzle.

From the foregoing, it is apparent that the objects of the presentinvention have been fully accomplished. As a result of this invention,an improved cement gun nozzle is provided for producing a highlycontrolled delivery with very little rebound and dust. By the provisionof a spiral or helical thread formation in the bore of the nozzle, aspiral twist or rifling motion is imparted to the cementitious mixture.By gradually tapering the bore toward its outlet end, a choking actionis effected to minimize spreading of the ingredients issuing from thenozzle. By forming the nozzle of a plastic resiliently yieldablematerial such as urethane, the necessity of grounding the nozzle iseliminated and the useful life of the nozzle is extended by the wear andabrasion resistance of such material. Also, the nozzle is of alightweight construction, easy to manufacture and convenient to handleduring use. Because of the resiliency of the material of which thenozzle is formed, the sizes of the liquid flow passages leading to thebore of the nozzle can be easily varied by merely adjustably threading ahose coupling or a liquid injecting head into or out of the nozzleinlet. The liquid flow control feature and the rifling action resultingfrom the spiral thread formation insures a thorough mix of theingredients with the liquid to produce a mix of optimum density andconsistency.

Preferred embodiments of this invention having been described in detail,it is to be understood that this has been done by way of illustrationonly.

The claims:

1. An adaptor comprising: a body formed of a resiliently yieldableplastic material having a bore therethrough, a threaded openingcommunicating with said bore, said opening having a diameter larger thansaid bore to define an annular seat therebetween, said seat beingprovided with means defining a series of passages communicating withsaid bore, an annular manifold passage spaced radially outwardly of saidbore communicating with said series of passages, and an inlet passagecommunicating with said annular manifold passage, said means definingsaid passages comprising a plurality of projections compressible forvarying the size of said passages.

2. An adaptor according to claim 1, wherein said resiliently yieldableplastic material is urethane.

3. An adaptor according to claim 1, including a second threaded openingin axially spaced relation to said first threaded opening andcommunicating with said bore for defining an outlet therefor engagablewith a nozzle.

4. An adaptor according to claim 1, including metallic means imbedded insaid body for reinforcing the same.

5. An adaptor comprising: a body formed of a resiliently yieldableplastic material having a bore therethrough, a threaded openingcommunicating with said bore, said opening having a diameter larger thansaid bore to define an annular seat there-between, said seat beingprovided with means defining a series of passages communicating withsaid bore, an annular manifold passage spaced radially outwardly of saidbore communicating with said series of passages, and an inlet passagecommunicating with said annular manifold passage, said passages definingmeans comprising a plurality of teeth each lying in an inclined planewhereby deflection of said teeth varies the size of said passages.

\ 6. An adaptor according to claim 5, wherein said resiliently yieldableplastic material is urethane.

1. An adaptor comprising: a body formed of a resiliently yieldableplastic material having a bore therethrough, a threaded openingcommunicating with said bore, said opening having a diameter larger thansaid bore to define an annular seat therebetween, said seat beingprovided with means defining a series of passages communicating withsaid bore, an annular manifold passage spaced radially outwardly of saidbore communicating with said series of passages, and an inlet passagecommunicating with said annular manifold passage, said means definingsaid passages comprising a plurality of projections compressible forvarying the size of said passages.
 2. An adaptor according to claim 1,wherein said resiliently yieldable plastic material is urethane.
 3. Anadaptor according to claim 1, including a second threaded opening inaxially spaced relation to said first threaded opening and communicatingwith said bore for defining an outlet therefor engagable with a nozzle.4. An adaptor according to claim 1, including metallic means imbedded insaid body for reinforcing the same.
 5. An adaptor comprising: a bodyformed of a resiliently yieldable plastic material having a boretherethrough, a threaded opening communicating with said bore, saidopening having a diameter larger than said bore to define an annularseat there-between, said seat being provided with means defining aseries of passages communicating with said bore, an annular manifoldpassage spaced radially outwardly of said bore communicating with saidseries of passages, and an inlet passage communicating with said annularmanifold passage, said passages defining means comprising a plurality ofteeth each lying in an inclined plane whereby deflection of said teethvaries the size of said passages.
 6. An adaptor according to claim 5,wherein said resiliEntly yieldable plastic material is urethane.